126 MORPHOLOGY AND TAXONOMY OF ADULT MALES 



Abdomen : 448-593 (509)0 long and 274-327 (304)0 wide. Tergites of segments I, II, III 

 and sometimes IV present ; those of segment VII and segments IX + X large. Sternites of 

 segment VIII weak. Ostioles well developed, 37-46 (40) o long at orifice. Abdominal setae 

 on each side : Dorsal setae 3-4 on segments I to VIII. Pleural setae 2-3 on segments I to VIII, 

 including one slightly longer seta on the latter segment. Ventral setae usually 1 and sometimes 

 2 on segment II, 2-3 on segments III to VII, and absent on segment VIII. Abdominal disc 

 pores : Segments I to VII with 1-3 (1-3), 1-2 (12), 1-3 (i-8). 1-3 (2-1), 1-3 (1-9), 1, and 1 

 pleural pores respectively. 



Setae of glandular pouch include a pair of 409-427 (421)0 long tail setae and one, 70-101 (82)0 

 long seta, i.e. the ratio length of the tail setae to the total length of the body 1 : 3-0-3-6 (3-3). 



Genital segment comparatively small ; subtriangular in dorsal view, with a broadly rounded 

 apex ; style more or less straight in lateral view. Penial sheath 122-137 ( I2 8)o long and 

 76-92 (79)0. wide ; i.e. the ratio length to width 1-5-1-7 (i-6) : 1, and the ratio its length to the 

 total body length 1 : io-o-n-6 (io-8). Basal ridge of penial sheath and its projection well 

 developed ; process of penial sheath absent. Aedeagus rather stout ; internal genital aperture 

 large. Setae of genital segment : Dorsally, 3 setae always present on each side near the base 

 of the style ; ventrally, 3-5 (3-8) setae, and 3-4 (3-3) minute setal sensilla occur on each side 

 of the penial sheath. 



Material : 10 specimens examined, collected by A. I. Ezz, on Croton sp., in 

 Cairo, Egypt, U.A.R., 22. xi. 1962. 



TRIONYMUS Berg, 1899 



Trionymus newsteadi (Green) 



(Text-figs. 19, 20) 



Winged forms only known ; newly emerged males light brown, becoming darker soon 

 afterwards, with dark brown or blackish eyes. They are narrow and slender, comparatively 

 large with short antennae and moderately long legs. When mounted 1 190-1498 (1372)0 long, 

 308-378 (350)0 wide at mesothorax and 2926-3542 (3318) o wing expanse. 



Body setae and disc pores : Antennae with numerous fleshy setae, about 310 long, and a 

 few slightly longer hair-like ones ; legs and main parts of the body with hair-like setae only. 

 Quadrilocular and occasionally quinquelocular disc pores, about 6y. in diameter, occur on the 

 thorax, abdomen and sometimes on the head. 



Head : Subtetrahedron ; subtriangular in dorsal and front views ; with a hardly indicated 

 ventral preocular depression. Length from apex to postoccipital ridge 116-125 (122)0. ; from 

 apex to neck 183-201 (192)0. ; width across the genae 214-250 (235)0. Dorsal arm of mid- 

 cranial ridge anteriorly separated from other arms and posteriorly meeting the postoccipital 

 ridge. Lateral and ventral arms forming a Y-shaped ridge. Postoccipital ridge anteriorly 

 confluent with preocular ridges. Preocular -\- interocular ridges joining the postocular ridge 

 below the ocellus ; preocular ridge with a well defined ventral rudiment. Preoral ridge slender. 

 Eyes : Dorsal simple eyes not projecting beyond the outer margins of the head in dorsal view ; 

 their corneae 21-27 (24)0 in diameter and separated by 1 13-134 (125)0, i.e. 4-6-6-1 (5-1) times 

 their corneae apart. Ventral simple eyes 24-34 (3°)^ m diameter and 24-31 (27)0 apart. 

 Lateral ocelli well developed. Cranial apophysis with truncate apex. Tentorial bridge slender. 

 Dorsal head setae 13-16 (14-7) on each side anterior to the postoccipital ridge ; each gena 

 usually with 4 and occasionally 3 or 5 genal setae (av. 3-8). Ventral head setae on each side : 

 1-2 (i-8) between the ventral eyes ; 11-16 (12-4) forming on both sides a transverse band in the 



